There are various types of manufacturing processes which involve the combination of a plurality of strands of material which during processing are combined with each other, with other materials or both. Where it is necessary to combine a plurality of such strands of material during either continuous or intermittent manufacturing operations, it is frequently convenient that the strands be coiled such as to provide the capability of continuously feeding out substantial lengths of the strands. In order to have available in a manageable form substantial lengths of coiled strands, it is commonly known to employ spools upon which the coiled strands are mounted for storage and from which the strands may be paid out by rotation of the spools about the longitudinal axis thereof.
One such example of the employment of spools to store and pay out strands is involved in the rubber industry where it is common to simultaneously employ a plurality of steel cords which are stored on and dispensed from spools. The spools are normally mounted in an array which is commonly referred to as a creel. While creels may differ in various details they commonly consist of an array of spindles which are mounted in a substantially vertical frame work having spindles which may project in both directions therefrom. The spools typically have a diameter of approximately ten inches and a longitudinal dimension of a foot, although other dimensions are employed in some instances. The spools have a hollow core which inwardly receives a creel spindle and which outwardly carries steel cord or other material repetitively coiled within the confines of the spool flanges. Creels commonly array the spindles in rectangular configurations projecting from the framework in arrangements which may conveniently have six spindles high and a multitude of spindles long or in some instances five spindles high and a multitude of spindles long. This type of arrangement places spindles from a position just above the ground to approximately six feet off the ground taking into account the necessary spacing between spindles as a result of the diameter of the spools which may be on the order of ten inches and of the necessary spacing between spindles to effect requisite control over pay out and tensioning of the strands.
Spools employed for steel cord are normally of a construction such that, while the spool is of relatively light metal material, the full spool with its capacity of steel cord approaching the radially outer extremity of the flanges may weigh on the order of forty to eighty pounds. The spools are normally packaged in standard rectangular shipping containers or cartons in which the spools are tightly packed in circumferential engagement with adjacent spools with the core or longitudinal axis vertically aligned. Cartons are commonly sized such as to receive three spool by four spool layers arranged in three layers constituting a total of 36 spools. In some instances, the containers may accommodate 72 spools having a reduced axial length.
In many manufacturing operations the cartons or containers are positioned proximate to the creels and an operator manually removes empty spools from the spindles and replaces them with full spools of steel cord. While manual loading of the creels is prossible, it has the disadvantage that over the period of a work day a creel operator may become sufficiently fatigued, particularly in relation to the placement of spools on the higher spindles, that the overall loading time for creels may become excessively long. In addition, the size and strength of a creel operator becomes highly significant in effecting the loading of spools over a period of time. In order to attempt to obviate a high degree of reliance on the size and strength of creel operators, efforts have been made to employ hoists to facilitate the lifting of individual spools. In this regard, the packaging of the spools in rectangular shipping containers becomes a significant factor. In particular, grasping devices employed with hoists have been constructed to engage either the upper flange of the spools or the opening of the hollow core of the spools; however, the grasping of the spools in this fashion has certain undesirable implications. In either instance where a spool is grasped by either the central opening or the flange, it is necessary that the flange of the spool opposite the flange being gripped be inserted onto the spindle. Since the spools on one side of a creel commonly rotate in one direction to pay out cord and spools on the other side or on other creels may rotate in the opposite direction, it is necessary that spools be double handled or the container of spools be inverted in order to effect loading in all situations with end gripping apparatus of this type. The flange gripping hoist devices have the additional disability that with the grasping of one flange and the relatively flimsy construction of the spool flanges, a spool may be distorted or damaged to such an extent that it will not operate properly on a creel spindle or is incapable of being securely retained by such hoist gripping devices. As a result of these various problems attendant efforts to partially mechanize the loading of spools on a creel, there remain substantial numbers of installations which are manually loaded or where hoist assisted grasping devices are employed only a portion of the time or by some operators. Certainly no single creel loading device has proved to have sufficient capability and flexibility to gain wide acceptance in the handling of spools of substantial weight such as those employed to coil steel cord.